古气候定量重建是古气候学研究的核心目标。孢粉因其本身具有的优势，已成为古气候定量重建研究中最直接、最可信的代用指标之一。基于中国西南地区在重建古气候方面具有的重要性，及该区孢粉现代过程与孢粉-气候定量重建方面的研究现状，本项申请拟从捕获器、表土与湖泊表泥三方面系统开展孢粉现代过程研究；利用多种转换函数模型、最佳类比法等构建具有区域特色的孢粉-气候定量关系模型；选择位于不同海拔、不同纬度，且受人类活动影响强度不同的滇西北天才湖、泸沽湖和洱海、滇西南腾冲青海湖和滇中的滇池开展约2万年来高分辨率的孢粉研究；利用已构建的孢粉-气候定量模型准确定量重建中国西南地区近2万年来的温度和降水变化。该研究将补充和完善我国现代孢粉数据库在西南地区已有数据量的不足、填补本区基于孢粉的气候定量重建研究的空白；定量重建的温度和降水序列有利于全面理解气候变化机制，对认识全球气候变化的性质与发展趋势具有非常重要的意义。

Quantitative reconstruction of paleoclimate is the core goal of paleoclimate research. Pollen has become one of the most direct and reliable proxies in paleoclimate quantitative reconstruction because of its advantages. Based on importance of southwestern China in paleoclimate reconstruction and research status on modern pollen process and pollen-climate quantitative reconstruction in this area, this project will study systematically modern pollen process from three aspects: trap, surface soil, and surface lake sediment. And then to construct a quantitative pollen-climate relationship model with regional characteristics by using various transformation function models and modern analogue techniques. Tiancai, Erhai, and Lugu Lakes in northwestern Yunnan Province, Qinghai Lake in southwestern Yunnan Province, and Dianchi Lake in middle Yunnan Province located at different altitude, different latitude, and affected by different human activity intensity will be selected to perform high-resolution pollen study since ~20 ka. Then temperature and precipitation sequences since ~20 ka in southwestern China will be accurately and quantitatively reconstructed by using the established pollen-climate quantitative model. This study will complement and perfect Chinese modern pollen database, where the number of the existing modern pollen data in southwestern China is not enough. This study will also fill the blank of quantitative paleoclimate reconstruction in southwestern China based on pollen. The temperature and precipitation sequences reconstructed quantitatively are helpful to understand mechanism of climate change in an all-round way, and it is of great significance to recognize nature and development trend of global climate change.